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    <title>Document</title>
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<body>
    <script>
            //基本数据类型：String Boolean Number Null Underfined Symbol
// let res = Symbol('尚硅谷')
// let res1 = Symbol('尚硅谷')
// console.log(res === res1)  //Symbol 里面的值是唯一的
let key1 = Symbol('1')
const obj = {
    a :1,
    nb :2,
    [Symbol('c')] :1,
    [Symbol('d')] :2,
}
for(let i in obj){
    console.log(i)
}
console.log(Object.getOwnPropertySymbols(obj))
    </script>

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